KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
KnowledgeAgent kAgent = createKAgent( kbase, false );
ChangeSetHelperImpl cs = new ChangeSetHelperImpl();
FileSystemResource f = (FileSystemResource) ResourceFactory.newFileResource(res);
f.setResourceType( ResourceType.DRL );
cs.addNewResource( f );
kAgent.applyChangeSet( cs.getChangeSet() );
ksession = kAgent.getKnowledgeBase().newStatefulKnowledgeSession();